Thread: Help needed: Sky Watcher 10" Dob can only focus on very close objects
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Old 20-12-2016, 10:02 AM
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doppler (Rick)
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Join Date: Nov 2012
Location: Mackay
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You have to include the distance from the secondary to the end of the eyepiece for the total focal length. My 1200mm fl solid tube is 900mm from the mirror to centre of focuser tube and 300mm from centre of diagonal to eyepiece tip.
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Last edited by doppler; 20-12-2016 at 10:27 AM.
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